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The Research of the Equation Model on the System-level Fault Diagnosis

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湖南大学学报（自然科学版） 2000年第S2期27卷 148-157页

作者： Hengnong Xuan1, Dafang Zhang2. Yue Wu3. Minwei He4 (1,4: dept. of Computer, Wuyi University, Jiangmen, Guangdong, 52.02., china (2. dept. of Computer, Hunan University, Changsha, 410082. china ) (3. institute of Computer Science and Engineering, Univers

In this paper we propose an equation model of system-level fault diagnoses, and construct corresponding theory and algorithms. People can turn any PMC model on ex-test into an equivalent equation (or a system of equations), and find all consistent fault patterns based on the equation model. We can also find all fault patterns, in which the fault node numbers are less than or equal to t without supposing t-diagnosable. It is not impossible for all graphic models.

关键词： PMC model equation model ex-test system-level fault diagnosis diagnostic algorithm

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时间序列稳定协和性的数值分析

数值计算与计算机应用 2004年第4期25卷 269-274页

作者：吕纯濂陈舜华南京信息工程大学数学系南京信息工程大学应用气象系

Cointegration analysis for time series involves the solution of a generalized eigenproblem involving moment matrices and inverted moment matrices. These formulae are unsuitable for actual computations because the condition numbers of the resulting matrices are unnecessarily increased. The special structure of the cointegration procedure is used to achieve numerically stable computations, based on QR and singular value decompositions.

关键词：时间序列稳定协和性标准算法极大似然估计数理统计广义特征

无源定位与数据融合技术在辐射源目标跟踪中的应用

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系统工程与电子技术 2003年第8期25卷 946-948,970页

作者：刘以安陈松灿刘同明韩斌南京航空航天大学信息科学与技术学院江苏南京210016 华东船舶工业学院电子与信息系江苏镇江212003

在多机动辐射源无源定位与跟踪系统中 ,因受低空杂波、电子干扰和雷达自身探测精度等因素影响 ,易使无源定位的数据不精确、不可靠 ,甚至相互矛盾 ,结果造成跟踪系统失效。针对这一情况 ,首先应用测向测时差定位法 ,处理机动辐射源的无... 详细信息

在多机动辐射源无源定位与跟踪系统中 ,因受低空杂波、电子干扰和雷达自身探测精度等因素影响 ,易使无源定位的数据不精确、不可靠 ,甚至相互矛盾 ,结果造成跟踪系统失效。针对这一情况 ,首先应用测向测时差定位法 ,处理机动辐射源的无源定位问题 ;然后在此基础上 ,应用数据融合技术进一步提高系统的定位与跟踪精度、可靠性和防御作战能力。仿真结果表明 ,该方法是有效。

关键词：无源定位时差定位测向测时差定位数据融合

Remote Sensing Analysis of the Suspended Sediment Transport in Lingdingyang

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china Ocean Engineering 1992年第3期7卷 331-349页

作者： You Yuming Hou Min Senior Engineer, River and Harbour Department, nanjing Hydraulic Research institute, 2.002., nanjing Assistant Engineer, River and Harbour Department, nanjing Hydraulic Research institute, 2.002., nanjing River & Harbour dept. Nanjing Hydraulic Research Inst. 210029 Nanjing China

The data of landsat TM of multi-temporal for Lingdingyang Estuary, Pearl River in china is firstly used with suspended sediment concentration of field measurement to establish a correlative model equation. After the ratio processing of TM data and atmospheric correction, the images of suspended sediment concentration of different temporals are exported from the image processing systems AREIS II and III. These images express the characteristics of suspended sediment distribution, the mode of sediment transport and the extent of dispersion under the actions of tidal current and wind condition of different seasons.

关键词： remote sensing suspended sediment concentration sediment transport estuary

PULSED Nd-YAG LASER WELDING OF AN AI-SiC_p METAL MATRIX COMPOSITE

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Chinese Journal of Aeronautics 1997年第1期10卷 75-80页

作者： Xu Jiukua Jiang Chengyu(Mechanical Engineering institute, nanjing University of Aeronauticsand Astronautics, nanjing, {3.0016, china)Yu Damin Liu Weicheng(Department of Manufacturing Engineering, Hong Kong Polytechnic University) Mechanical Engineering institute Nanjing Univ. Aero. and Astronaut. Nanjing 210016 China dept. of Manufacturing Engineering Hong Kong Polytechnic University Hong Kong

A study is presented of the laser welding behaviour of an SiC particulate re-inforced Al-alloy comPOsite using a pulsed Nd-YAG laser. The influences of laser weldingparameters of laser intensity, pulse duration and the beamjs focus position on the dept. ofweld penetration as well as the size of weld bead width were investigated. A typical mi-crostructure of a weld section reveals that the three distinct zones are present. Cracks andporosity were fOund to be two major defects in laser welded metal matrix composites(MMC). These investigations have led to an optimum welding condition proposed forlaser welding of SiC partiulate reinforced aluminium alloy comPosites with minimum de-fects.

关键词： metal matrix composites laser welding laser intensity peak power

Interhemispheric atmospheric mass oscillation and its relation to interannual variations of the Asian monsoon in boreal summer

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Science china Earth Sciences 2010年第9期53卷 1343-1350页

作者： LU ChuHan, GUAN ZhaoYong & CAI JiaXi Key Laboratory of Meteorological Disaster of Ministry of Education and College of Atmospheric Sciences, nanjing University of Information Science & Technology, nanjing 21004.,{2. 1. Key Laboratory of Meteorological Disaster of Ministry of Education and College of Atmospheric Sciences Nanjing University of Information Science & Technology Nanjing 210044 China

Using NCEP/NCAR reanalysis and precipitation records of Chinese stations, we have investigated the relationship of interhemispheric oscillation of air mass (IHO) with global lower-level circulation and monsoon anomalies in boreal summer. Our results show that the summer IHO explains a greater portion of variance in the abnormal distribution of atmospheric mass over 3.°S-60°N as well as the Antarctic. The IHO strongly correlates to the variations of sea level pressure (SLP) in these regions. It is shown that IHO has some influences on both atmospheric mass transports and water vapor fluxes over 3.°S-60°N in association with three anomalous cyclonic circulations over land areas of the eastern hemisphere, which is in close relation to the changes in summer monsoon intensity in eastern Asia and western Africa. Composites of summer rainfall anomalies in china for high and low IHO-index years indicate that the eastern Asian summer monsoon is more intense, with positive precipitation anomaly centers in northern and northeastern parts of china, as opposed to the negative center over the mid-lower reaches of the Yangtze River (MLRYR) in stronger IHO years. In weak IHO years, a feeble summer monsoon appears in eastern Asia, leading to positive center of precipitation anomalies displaced into the MLRYR. Furthermore, a teleconnection in wind fields between the western African and eastern Asian monsoon regions was observed in the middle and higher troposphere in the scenario of IHO. The anomalous cyclonic (anticyclonic) circulations along the path of this Africa-East Asia teleconnection were found to be just over the diabatic heating (cooling) centers, suggesting that diabatic forcings are responsible for the formation of this Africa-East Asia teleconnection.

关键词： interhemispheric oscillation Asian monsoon precipitation china boreal summer

Study on Reconstruction of Heat Flux in Moving Boundary

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Study on Reconstruction of Heat Flux in Moving Boundary

Forecasting Nonlinear Time Series with Genetic Algorithms Genetic Algorithms and Symbolic Form

2.12.National Conference on Information Technology and Computer Science

作者： Zhijian Wu institute of meteorology and Oceangraphy PLA University of Science Technology {2.,{3. Jing Feng institute of meteorology and Oceangraphy PLA University of Science Technology {2.,{3. Xueyan Zhang institute of meteorology and Oceangraphy PLA University of Science Technology {2.,{3. Aixia Zhou institute of meteorology and Oceangraphy PLA University of Science Technology {2.,{3.

The initial boundary value problem for parabolic equation with Neumann boundary condition is a kind of classical problem in partial differential *** this paper,we consider a heat inverse problem with moving *** introducing a density function for potential method,thisproblem is essentially converted into solving an integral equation of the first kind with respect to the density function,which can be solved by the Tikhonov regularizing *** function method is used to determine the regularizing *** results are presented to support our inversion schemes.

关键词： heat equation potential scheme heat flux regularization numerics

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Forecasting Nonlinear Time Series with Genetic Algorithms Ge...

Planar cubic hybrid hyperbolic polynomial curve and its shape classification

2.10 Second IITA International Conference on Geoscience and Remote Sensing (IITA-GRS 2.10)

作者： Sheng Zheng institute of meteorology PLA university of science of technology {2. {3. Zhao Xiao-feng institute of meteorology PLA university of science of technology {2. {3.

A genetic algorithm（GA） programmed to approximate the functional relation,in symbolic form,that describes the behavior of a time *** GA formalism proposed here utilizes the ’’postfix’’ representation with a view to reduce the procedural complexities and the "elitist mating’’ scheme to produce fitter offspring *** initial population of potential solutions is subjected to an evolutionary process described by selection,reproduction and mutation processes which are repeated over generations until an optimum individual is finally *** GA was proved useful in obtaining functional forms describing accurately the evolution of the nonlinear time series.

关键词： genetic algorithm forecasting nonlinear time series.

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Progress in Natural Science:Materials International 2004年第1期14卷 42-47页

作者： WANG Guozhao 1,2. * and YANG Qinmin 1,2. (1. institute of Computer Graphics and Image Processing, 2. Department of Mathematics, Zhejiang University, Hangzhou 3.002., china) Zhejiang Univ Inst Comp Graph & Image Proc Hangzhou 310027 Peoples R China Zhejiang Univ Dept Math Hangzhou 310027 Peoples R China

The planar cubic hybrid hyperbolic polynomial curves and cubic H Bézier curves are presented. The conditions leading to inflection points and singularities (cusps and loops) are investigated and the shape of these curves is classified. The conclusions enable us to detect inflection points and singularities and get an idea of how to preserve the fair shape when designing such curves.

关键词： hybrid hyperbolic polynomial curve H-Bézier curve shape classification inflection points singularities